Dear Dipyaman,
I my self seen the Loco pilot rest rooms at SCMN. As its the end the ECoR zone LP change their duties VZM is for water filling only. Any ways i dont have any idea about Duranto. But for other diverted trains i am 100% sure all will stop at SCMN. I will post Amaravati pics and video tonight as a reference. They bought it to PF of SCMN and BZA-Rayagada passenger came to loop line that day. Its not only me...there are 4 regular travelers told me that Amaravati and all diverted trains stops at SCMN.